Mechanistic insights into HIV-mediated heart failure with preserved ejection fraction

艾滋病毒感染者现在的寿命更长，并患有许多慢性病，这些疾病发生在艾滋病毒感染者身上 在更高的比率和更早的年龄，并继续发展，尽管抑制性抗逆转录病毒治疗（ART）。 PLWH中常见的异常之一是射血分数保留的心力衰竭（HFpEF）， 定义为左心室射血分数为50%或更高的舒张功能障碍。HFpEF的研究进展 与全因死亡率的增加相关，突出了临床意义 这种混乱。HFpEF在PLWH中的细胞机制还不完全清楚，但慢性炎症， 遗传易感性和ART的副作用。在本提案中，我们将解决 使用两种系统对HIV相关HFpEF机制的认识存在根本差距：1）已经 从恒河猴分离的心肌细胞建立模型，模拟CCR 5后的HFpEF病理 配体暴露，和2）人诱导多能干细胞衍生的心肌细胞（hiPSC-CM）。然后我们将 通过用细胞因子处理细胞或将它们暴露于炎性介质中， 环境。我们的中心假设是心肌细胞中的线粒体发病机制是 由HIV相关的全身性炎症引发，导致HFpEF，新的治疗方法可以 对抗细胞紊乱我们还假设，易感性的异质性， HFpEF是由于对这些病理机制的遗传偏好的差异。研究我们 假设，我们提出了两个目标。在目的1中，我们将确定HFpEF的发病机制， 心肌细胞分离的恒河猴心肌细胞和来自五个未感染、未感染和未感染的hiPSC-CM的对照hiPSC-CM。 HFpEF供体将暴露于使用三种系统的慢性炎症的体外模型： CCR 5配体，2）微生物易位，和3）非CCR 5配体细胞因子的添加，所有这些都已经被证实。 证明在PLWH中的改变独立于病毒复制。然后我们将评估这些影响 通过测量钙瞬变对心肌细胞松弛和功能的操作，此外， 线粒体功能和ROS（作为细胞损伤的标志物）。我们还将治疗hiPSC-CM和孤立的 心肌细胞与ART，以排除ART舒张功能障碍的贡献。最后，我们将生成 来自10名HIV患者的hiPSC-CM，5名具有HFpEF，5名不具有HFpEF，并进行RNA测序以鉴定 用于表征HFpEF易感性遗传基础的候选基因。在目标2中，我们将确定 新药是否保护心肌细胞免受引起HFpEF的细胞发病机制的影响。我们将揭露 如目的1中所述，将来自猕猴的心肌细胞和hiPSC-CM诱导至炎症环境，并将 评估用炎症和ROS下游的药物治疗（即，磷酸二酯酶5/9 抑制剂、可溶性鸟苷酸环化酶刺激剂、利钠肽和抗氧化剂）改善钙 瞬变和线粒体功能。

Persons living with HIV (PLWH) now live longer and suffer from many chronic conditions, which occur in PLWH at a higher rate and at an earlier age, and continue to develop despite suppressive antiretroviral therapy (ART). One of the abnormalities commonly found in PLWH is heart failure with preserved ejection fraction (HFpEF), defined as diastolic dysfunction with left ventricular ejection fraction of 50% or more. The development of HFpEF in the general population is associated with an increase in all-cause mortality, highlighting the clinical significance of this disorder. The cellular mechanism of HFpEF in PLWH is not totally understood, but chronic inflammation, genetic predisposition, and side effects of ART have been proposed. In this proposal, we will address the fundamental gap in knowledge of the mechanism of HIV-associated HFpEF using two systems: 1) already established model of isolated cardiomyocytes from rhesus monkey that mimic HFpEF pathology following CCR5 ligand exposure, and 2) human induced pluripotent stem cell-derived cardiomyocytes (hiPSC-CMs). We will then simulate chronic inflammation in vitro by treating the cells with cytokines or exposing them to an inflammatory milieu. Our central hypothesis is that mitochondrial pathogenetic mechanisms in cardiomyocytes are triggered by HIV-associated systemic inflammation to cause HFpEF, and that novel therapies can counter the cellular derangements. We also hypothesize that the heterogeneity of susceptibility to HFpEF is due to differences in genetic predilection to these pathologic mechanisms. To study our hypothesis, we propose two aims. In Aim 1, we will determine the pathogenetic mechanisms of HFpEF in cardiomyocytes. Isolated rhesus monkey cardiomyocytes and control hiPSC-CMs from five non-infected, non- HFpEF donors will be exposed to an in vitro model of chronic inflammation using three systems: 1) addition of CCR5 ligands, 2) microbial translocation, and 3) addition of non-CCR5 ligand cytokines, all of which have been demonstrated to be altered in PLWH independent of viral replication. We will then assess the effects of these manipulations on cardiomyocyte relaxation and function by measuring calcium transients, in addition to mitochondrial function and ROS (as markers of cellular injury). We will also treat hiPSC-CMs and isolated cardiomyocytes with ART to rule out a contribution of ART to diastolic dysfunction. Finally, we will generate hiPSC-CMs from 10 HIV patients, 5 with, and 5 without HFpEF and perform RNA-sequencing to identify candidate genes for characterization of the genetic basis of susceptibility to HFpEF. In Aim 2, we will determine whether novel drugs protect cardiomyocytes against the cellular pathogenesis causing HFpEF. We will expose cardiomyocytes from macaque and hiPSC-CMs to an inflammatory environment as described in Aim 1, and will assess whether treatment with drugs downstream of inflammation and ROS (i.e., phosphodiesterase 5/9 inhibitors, soluble guanylate cyclase stimulators, natriuretic peptides, and antioxidants) improve calcium transients and mitochondrial function.